sgl-router: experimental Rust HTTP router for SGLang worker pools (#25851)

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

experimental/sgl-router/tests/proxy/main.rs

@@ -0,0 +1,19 @@
+// SPDX-FileCopyrightText: Copyright (c) 2026 The SGLang Authors
+// SPDX-License-Identifier: Apache-2.0
+
+//! Full HTTP proxy integration tests.
+//!
+//! Each submodule spins up the router via `build_router(AppContext)` and
+//! drives real requests through a `common::mock_worker::MockWorker`
+//! backend. For component-scope tests that don't need the router, see
+//! `tests/component/`.
+
+mod common;
+
+mod chat_routing;
+mod failover;
+mod graceful_shutdown;
+mod header_forwarding;
+mod pd_bootstrap_injection;
+mod pd_pool_isolation;
+mod timeout;